Monitor all IE use on your network - Windows Shareware $62.
With SilentNight IE Watch you get the following. A server part you will have to install to one computer within your lan, and a client that must be copied to all computers you want to surveillance. The client dont need any installation, just copy it to the computer you want, and then start it once.

SilentNight IE Watch 1.0 13-Mar-05 English 55 KB

Thats it. From now of it will take care of it self. The client will from now of send the server a message every time Internet Explorer is used on that computer. The message delivered is: Computername, IP, User, Time of the site visit and finally the site visited(url). The client is runned in stealth mode, and to stop it you will need to know the right key combination and a password.